1. Field of the Invention
The present invention relates to novel chemically modified succinoglycans and to industrial compositions comprised thereof.
According to the present invention "succinoglycan" includes the family of polysaccharides of bacterial origin which contain, in addition to structural units derived from galactose and from glucose, structural units derived from succinic, pyruvic and, optionally, acetic acids, or from the salts of such acids.
2. Description of the Prior Art
It is known to this art that the different microorganism which are suitable for producing the above succinoglycans include, in particular, the bacteria of the Pseudomonas, Rhizobium, Alcaligenes and Agrobacterium genera.
Certain particular succinoglycans described in the literature have very desirable rheological properties under severe conditions of temperature or of pH.
Indeed, these succinoglycans exhibit rheological properties comparable to those of xanthan gum and are, furthermore, characterized by an increased stability to temperature, to acid and basic pHs and in strongly saline media.
This type of succinoglycan thus proves to be an attractive substitute for xanthan gum in industrial fields as varied as, for example, agrochemistry, the farm produce industry, the petroleum industry and cosmetics.
Various industrial applications of the succinoglycans are also known to this art. However, these applications exclusively employ succinoglycan aqueous solutions and not succinoglycan aqueous gels. A gel, however, would be very particularly desirable by reason of its greater capacities as a suspending agent and as a stabilizer, both in foodstuffs, perishable comestibles and in cosmetics.
Succinoglycan gels are described in EP-251,638, but these are essentially gels prepared via the crosslinking of succinoglycans by metal cations. These metal cations remain in the final succinoglycan gel which gels are thus unsuitable/incompatible for foodstuff applications.